package io.quarkus.kogito.deployment;

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.function.BiFunction;
import java.util.stream.Collectors;

import org.drools.compiler.commons.jci.compilers.CompilationResult;
import org.drools.compiler.commons.jci.compilers.JavaCompiler;
import org.drools.compiler.commons.jci.compilers.JavaCompilerSettings;
import org.drools.compiler.compiler.io.memory.MemoryFileSystem;
import org.drools.compiler.kproject.models.KieModuleModelImpl;
import org.drools.modelcompiler.builder.JavaParserCompiler;
import org.jboss.jandex.ClassInfo;
import org.jboss.jandex.CompositeIndex;
import org.jboss.jandex.DotName;
import org.jboss.jandex.Index;
import org.jboss.jandex.IndexView;
import org.jboss.jandex.Indexer;
import org.jboss.jandex.MethodInfo;
import org.kie.api.builder.model.KieModuleModel;
import org.kie.internal.kogito.codegen.Generated;
import org.kie.kogito.Model;
import org.kie.kogito.codegen.ApplicationGenerator;
import org.kie.kogito.codegen.GeneratedFile;
import org.kie.kogito.codegen.decision.DecisionCodegen;
import org.kie.kogito.codegen.di.CDIDependencyInjectionAnnotator;
import org.kie.kogito.codegen.process.ProcessCodegen;
import org.kie.kogito.codegen.process.persistence.PersistenceGenerator;
import org.kie.kogito.codegen.rules.IncrementalRuleCodegen;

import io.quarkus.arc.deployment.GeneratedBeanBuildItem;
import io.quarkus.builder.item.BuildItem;
import io.quarkus.deployment.annotations.BuildProducer;
import io.quarkus.deployment.annotations.BuildStep;
import io.quarkus.deployment.builditem.ArchiveRootBuildItem;
import io.quarkus.deployment.builditem.CombinedIndexBuildItem;
import io.quarkus.deployment.builditem.FeatureBuildItem;
import io.quarkus.deployment.builditem.LaunchModeBuildItem;
import io.quarkus.deployment.builditem.LiveReloadBuildItem;
import io.quarkus.deployment.builditem.nativeimage.NativeImageResourceBuildItem;
import io.quarkus.deployment.builditem.nativeimage.ReflectiveClassBuildItem;
import io.quarkus.deployment.builditem.nativeimage.ReflectiveHierarchyIgnoreWarningBuildItem;
import io.quarkus.deployment.index.IndexingUtil;
import io.quarkus.runtime.LaunchMode;

public class KogitoAssetsProcessor {

    private final transient String generatedClassesDir = System.getProperty("quarkus.debug.generated-classes-dir");
    private final transient String appPackageName = "org.kie.kogito.app";
    private final transient String persistenceFactoryClass = "org.kie.kogito.persistence.KogitoProcessInstancesFactory";
    private final transient String metricsClass = "org.kie.addons.monitoring.rest.MetricsResource";

    @BuildStep(providesCapabilities = "io.quarkus.kogito")
    FeatureBuildItem featureBuildItem() {
        return new FeatureBuildItem(FeatureBuildItem.KOGITO);
    }

    public void generatePersistenceInfo(ArchiveRootBuildItem root,
            BuildProducer<GeneratedBeanBuildItem> generatedBeans,
            IndexView index,
            LaunchModeBuildItem launchMode,
            BuildProducer<NativeImageResourceBuildItem> resource) throws IOException {

        Path projectPath = getProjectPath(root.getArchiveLocation());
        ClassInfo persistenceClass = index
                .getClassByName(createDotName(persistenceFactoryClass));
        boolean usePersistence = persistenceClass != null;
        List<String> parameters = new ArrayList<>();
        if (usePersistence) {
            for (MethodInfo mi : persistenceClass.methods()) {
                if (mi.name().equals("<init>") && !mi.parameters().isEmpty()) {
                    parameters = mi.parameters().stream().map(p -> p.name().toString()).collect(Collectors.toList());
                    break;
                }
            }
        }

        Collection<ClassInfo> modelClasses = index
                .getAllKnownImplementors(createDotName(Model.class.getCanonicalName()));

        PersistenceGenerator persistenceGenerator = new PersistenceGenerator(new File(projectPath.toFile(), "target"),
                modelClasses, usePersistence,
                new JandexProtoGenerator(index, createDotName(Generated.class.getCanonicalName())),
                parameters);
        persistenceGenerator.setDependencyInjection(new CDIDependencyInjectionAnnotator());
        persistenceGenerator.setPackageName(appPackageName);

        Collection<GeneratedFile> generatedFiles = persistenceGenerator.generate();

        if (!generatedFiles.isEmpty()) {
            MemoryFileSystem trgMfs = new MemoryFileSystem();
            CompilationResult result = compile(root, trgMfs, generatedFiles, launchMode.getLaunchMode(),
                    root.getArchiveLocation());
            register(trgMfs, generatedBeans, (className, data) -> new GeneratedBeanBuildItem(className, data),
                    launchMode.getLaunchMode(), result, root.getArchiveLocation());
        }

        if (usePersistence) {
            resource.produce(new NativeImageResourceBuildItem("kogito-types.proto"));
        }
    }

    @BuildStep
    public List<ReflectiveHierarchyIgnoreWarningBuildItem> reflectiveDMNREST() {
        List<ReflectiveHierarchyIgnoreWarningBuildItem> result = new ArrayList<>();
        result.add(new ReflectiveHierarchyIgnoreWarningBuildItem(createDotName("org.kie.api.builder.Message$Level")));
        result.add(new ReflectiveHierarchyIgnoreWarningBuildItem(createDotName("org.kie.dmn.api.core.DMNContext")));
        result.add(new ReflectiveHierarchyIgnoreWarningBuildItem(createDotName("org.kie.dmn.api.core.DMNDecisionResult")));
        result.add(new ReflectiveHierarchyIgnoreWarningBuildItem(
                createDotName("org.kie.dmn.api.core.DMNDecisionResult$DecisionEvaluationStatus")));
        result.add(new ReflectiveHierarchyIgnoreWarningBuildItem(createDotName("org.kie.dmn.api.core.DMNMessage")));
        result.add(new ReflectiveHierarchyIgnoreWarningBuildItem(createDotName("org.kie.dmn.api.core.DMNMessage$Severity")));
        result.add(new ReflectiveHierarchyIgnoreWarningBuildItem(createDotName("org.kie.dmn.api.core.DMNMessageType")));
        result.add(
                new ReflectiveHierarchyIgnoreWarningBuildItem(createDotName("org.kie.dmn.api.feel.runtime.events.FEELEvent")));
        return result;
    }

    @BuildStep
    public void generateModel(ArchiveRootBuildItem root,
            BuildProducer<GeneratedBeanBuildItem> generatedBeans,
            CombinedIndexBuildItem combinedIndexBuildItem,
            LaunchModeBuildItem launchMode,
            LiveReloadBuildItem liveReload,
            BuildProducer<NativeImageResourceBuildItem> resource,
            BuildProducer<ReflectiveClassBuildItem> reflectiveClass) throws IOException {

        if (liveReload.isLiveReload()) {
            return;
        }

        Path targetClassesPath = root.getArchiveLocation();
        Path projectPath = getProjectPath(targetClassesPath);

        boolean generateRuleUnits = true;
        boolean generateProcesses = true;
        boolean generateDecisions = true;

        ApplicationGenerator appGen = createApplicationGenerator(projectPath, launchMode.getLaunchMode(), generateRuleUnits,
                generateProcesses, generateDecisions, combinedIndexBuildItem);
        Collection<GeneratedFile> generatedFiles = appGen.generate();

        if (!generatedFiles.isEmpty()) {

            Indexer kogitoIndexer = new Indexer();
            Set<DotName> kogitoIndex = new HashSet<>();

            MemoryFileSystem trgMfs = new MemoryFileSystem();
            CompilationResult result = compile(root, trgMfs, generatedFiles, launchMode.getLaunchMode(),
                    targetClassesPath);
            register(trgMfs, generatedBeans, (className, data) -> {

                IndexingUtil.indexClass(className, kogitoIndexer, combinedIndexBuildItem.getIndex(), kogitoIndex,
                        Thread.currentThread().getContextClassLoader(),
                        data);
                return new GeneratedBeanBuildItem(className, data);
            },
                    launchMode.getLaunchMode(), result, targetClassesPath);

            Index index = kogitoIndexer.complete();

            generatePersistenceInfo(root, generatedBeans, CompositeIndex.create(combinedIndexBuildItem.getIndex(), index),
                    launchMode, resource);

            reflectiveClass.produce(
                    new ReflectiveClassBuildItem(true, true, "org.kie.kogito.services.event.AbstractProcessDataEvent"));
            reflectiveClass.produce(
                    new ReflectiveClassBuildItem(true, true, "org.kie.kogito.services.event.ProcessInstanceDataEvent"));
            reflectiveClass.produce(
                    new ReflectiveClassBuildItem(true, true, "org.kie.kogito.services.event.impl.ProcessInstanceEventBody"));
            reflectiveClass.produce(
                    new ReflectiveClassBuildItem(true, true, "org.kie.kogito.services.event.impl.NodeInstanceEventBody"));
            reflectiveClass.produce(
                    new ReflectiveClassBuildItem(true, true, "org.kie.kogito.services.event.impl.ProcessErrorEventBody"));
            reflectiveClass.produce(
                    new ReflectiveClassBuildItem(true, true, "org.kie.kogito.services.event.UserTaskInstanceDataEvent"));
            reflectiveClass.produce(
                    new ReflectiveClassBuildItem(true, true, "org.kie.kogito.services.event.impl.UserTaskInstanceEventBody"));

            Collection<ClassInfo> dataEvents = index
                    .getAllKnownSubclasses(createDotName("org.kie.kogito.services.event.AbstractProcessDataEvent"));

            dataEvents.forEach(c -> reflectiveClass.produce(
                    new ReflectiveClassBuildItem(true, true, c.name().toString())));

        }

    }

    private Path getProjectPath(Path archiveLocation) {
        Path projectPath = archiveLocation.toString().endsWith("target" + File.separator + "classes")
                ? archiveLocation.getParent().getParent()
                : archiveLocation;

        return projectPath;
    }

    private CompilationResult compile(ArchiveRootBuildItem root, MemoryFileSystem trgMfs,
            Collection<GeneratedFile> generatedFiles,
            LaunchMode launchMode, Path projectPath)
            throws IOException {

        JavaCompiler javaCompiler = JavaParserCompiler.getCompiler();
        JavaCompilerSettings compilerSettings = javaCompiler.createDefaultSettings();
        compilerSettings.addClasspath(root.getArchiveLocation().toString());

        MemoryFileSystem srcMfs = new MemoryFileSystem();

        String[] sources = new String[generatedFiles.size()];
        int index = 0;
        for (GeneratedFile entry : generatedFiles) {
            String generatedClassFile = entry.relativePath().replace("src/main/java/", "");
            String fileName = toRuntimeSource(toClassName(generatedClassFile));
            sources[index++] = fileName;

            srcMfs.write(fileName, entry.contents());

            String location = generatedClassesDir;
            if (launchMode == LaunchMode.DEVELOPMENT) {
                location = Paths.get(projectPath.toString()).toString();
            }

            writeGeneratedFile(entry, location);

        }

        return javaCompiler.compile(sources, srcMfs, trgMfs,
                Thread.currentThread().getContextClassLoader(), compilerSettings);
    }

    private void register(MemoryFileSystem trgMfs, BuildProducer generatedBeans,
            BiFunction<String, byte[], ? extends BuildItem> bif, LaunchMode launchMode,
            CompilationResult result, Path projectPath) throws IOException {
        if (result.getErrors().length > 0) {
            StringBuilder errorInfo = new StringBuilder();
            Arrays.stream(result.getErrors()).forEach(cp -> errorInfo.append(cp.toString()));
            throw new IllegalStateException(errorInfo.toString());
        }

        for (String fileName : trgMfs.getFileNames()) {
            byte[] data = trgMfs.getBytes(fileName);
            String className = toClassName(fileName);
            generatedBeans.produce(bif.apply(className, data));

            if (launchMode == LaunchMode.DEVELOPMENT) {
                Path path = writeFile(Paths.get(projectPath.toString(), fileName).toString(), data);

                String sourceFile = path.toString().replaceFirst("\\.class", ".java");
                if (sourceFile.contains("$")) {
                    sourceFile = sourceFile.substring(0, sourceFile.indexOf("$")) + ".java";
                }
                KogitoCompilationProvider.classToSource.put(path,
                        Paths.get(sourceFile));
            }
        }
    }

    private Path writeFile(String fileName, byte[] data) throws IOException {
        Path path = Paths.get(fileName);
        if (!Files.exists(path.getParent())) {
            Files.createDirectories(path.getParent());
        }
        Files.write(path, data);

        return path;
    }

    private ApplicationGenerator createApplicationGenerator(Path projectPath, LaunchMode launchMode,
            boolean generateRuleUnits,
            boolean generateProcesses,
            boolean generateDecisions,
            CombinedIndexBuildItem combinedIndexBuildItem)
            throws IOException {

        Path srcPath = projectPath.resolve("src");
        boolean usePersistence = combinedIndexBuildItem.getIndex()
                .getClassByName(createDotName(persistenceFactoryClass)) != null;

        ApplicationGenerator appGen = new ApplicationGenerator(appPackageName, new File(projectPath.toFile(), "target"))
                .withDependencyInjection(new CDIDependencyInjectionAnnotator())
                .withPersistence(usePersistence)
                .withMonitoring(combinedIndexBuildItem.getIndex()
                        .getClassByName(createDotName(metricsClass)) != null);

        if (generateRuleUnits) {
            Path moduleXmlPath = projectPath.resolve("src/main/resources").resolve(KieModuleModelImpl.KMODULE_JAR_PATH);
            KieModuleModel kieModuleModel = null;
            if (Files.exists(moduleXmlPath)) {
                kieModuleModel = KieModuleModelImpl.fromXML(
                        new ByteArrayInputStream(
                                Files.readAllBytes(moduleXmlPath)));
            } else {
                kieModuleModel = KieModuleModelImpl.fromXML(
                        "<kmodule xmlns=\"http://www.drools.org/xsd/kmodule\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"/>");
            }

            appGen.withGenerator(IncrementalRuleCodegen.ofPath(srcPath))
                    .withKModule(kieModuleModel)
                    .withClassLoader(Thread.currentThread().getContextClassLoader());
        }

        if (generateProcesses) {

            appGen.withGenerator(ProcessCodegen.ofPath(projectPath))
                    .withPersistence(usePersistence)
                    .withClassLoader(Thread.currentThread().getContextClassLoader());
        }

        if (generateDecisions) {
            appGen.withGenerator(DecisionCodegen.ofPath(projectPath));
        }

        return appGen;
    }

    private String toRuntimeSource(String className) {
        return "src/main/java/" + className.replace('.', '/') + ".java";
    }

    private String toClassName(String sourceName) {
        if (sourceName.startsWith("./")) {
            sourceName = sourceName.substring(2);
        }
        if (sourceName.endsWith(".java")) {
            sourceName = sourceName.substring(0, sourceName.length() - 5);
        } else if (sourceName.endsWith(".class")) {
            sourceName = sourceName.substring(0, sourceName.length() - 6);
        }
        return sourceName.replace('/', '.');
    }

    private void writeGeneratedFile(GeneratedFile f, String location) throws IOException {
        if (location == null) {
            return;
        }
        String generatedClassFile = f.relativePath().replace("src/main/java", "");
        Files.write(
                pathOf(location, generatedClassFile),
                f.contents());
    }

    private Path pathOf(String location, String end) {
        Path path = Paths.get(location, end);
        path.getParent().toFile().mkdirs();
        return path;
    }

    private DotName createDotName(String name) {
        int lastDot = name.indexOf('.');
        if (lastDot < 0) {
            return DotName.createComponentized(null, name);
        }

        DotName lastDotName = null;
        while (lastDot > 0) {
            String local = name.substring(0, lastDot);
            name = name.substring(lastDot + 1);
            lastDot = name.indexOf('.');
            lastDotName = DotName.createComponentized(lastDotName, local);
        }

        int lastDollar = name.indexOf('$');
        if (lastDollar < 0) {
            return DotName.createComponentized(lastDotName, name);
        }
        DotName lastDollarName = null;
        while (lastDollar > 0) {
            String local = name.substring(0, lastDollar);
            name = name.substring(lastDollar + 1);
            lastDollar = name.indexOf('$');
            if (lastDollarName == null) {
                lastDollarName = DotName.createComponentized(lastDotName, local);
            } else {
                lastDollarName = DotName.createComponentized(lastDollarName, local, true);
            }
        }
        return DotName.createComponentized(lastDollarName, name, true);
    }

}
